s390/qeth: streamline TX buffer management

Consolidate the code that marks the current buffer to be flushed, and
let qeth_fill_buffer() advance the Output Queue's buffer cursor.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index e63e031..e08b924 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -3928,7 +3928,6 @@ static int qeth_fill_buffer(struct qeth_qdio_out_q *queue,
 {
        struct qdio_buffer *buffer = buf->buffer;
        bool is_first_elem = true;
-       int flush_cnt = 0;
 
        __skb_queue_tail(&buf->skb_list, skb);
 
@@ -3949,24 +3948,22 @@ static int qeth_fill_buffer(struct qeth_qdio_out_q *queue,
 
        if (!queue->do_pack) {
                QETH_CARD_TEXT(queue->card, 6, "fillbfnp");
-               /* set state to PRIMED -> will be flushed */
-               atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
-               flush_cnt = 1;
        } else {
                QETH_CARD_TEXT(queue->card, 6, "fillbfpa");
                if (queue->card->options.performance_stats)
                        queue->card->perf_stats.skbs_sent_pack++;
-               if (buf->next_element_to_fill >=
-                               QETH_MAX_BUFFER_ELEMENTS(queue->card)) {
-                       /*
-                        * packed buffer if full -> set state PRIMED
-                        * -> will be flushed
-                        */
-                       atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
-                       flush_cnt = 1;
-               }
+
+               /* If the buffer still has free elements, keep using it. */
+               if (buf->next_element_to_fill <
+                   QETH_MAX_BUFFER_ELEMENTS(queue->card))
+                       return 0;
        }
-       return flush_cnt;
+
+       /* flush out the buffer */
+       atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
+       queue->next_buf_to_fill = (queue->next_buf_to_fill + 1) %
+                                 QDIO_MAX_BUFFERS_PER_Q;
+       return 1;
 }
 
 static int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue,
@@ -3982,7 +3979,6 @@ static int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue,
         */
        if (atomic_read(&buffer->state) != QETH_QDIO_BUF_EMPTY)
                return -EBUSY;
-       queue->next_buf_to_fill = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;
        qeth_fill_buffer(queue, buffer, skb, hdr, offset, hd_len);
        qeth_flush_buffers(queue, index, 1);
        return 0;
@@ -4040,10 +4036,9 @@ int qeth_do_send_packet(struct qeth_card *card, struct qeth_qdio_out_q *queue,
                        }
                }
        }
-       tmp = qeth_fill_buffer(queue, buffer, skb, hdr, offset, hd_len);
-       queue->next_buf_to_fill = (queue->next_buf_to_fill + tmp) %
-                                 QDIO_MAX_BUFFERS_PER_Q;
-       flush_count += tmp;
+
+       flush_count += qeth_fill_buffer(queue, buffer, skb, hdr, offset,
+                                       hd_len);
        if (flush_count)
                qeth_flush_buffers(queue, start_index, flush_count);
        else if (!atomic_read(&queue->set_pci_flags_count))